Association of anticyclic citrullinated peptide antibodies with extra-articular manifestations, gender, and tabagism in rheumatoid arthritis patients from southern Brazil.

Gender and environmental factors are known to influence the clinical heterogeneity and outcome of rheumatoid arthritis (RA). Some variables have been suggested to be associated with the severity of the disease, which can be of great value in the correct management of RA patients. The purpose of this study was to investigate the associations among anticyclic citrullinated antibody (anti-CCP2) positivity, extra-articular manifestations (EAM), gender, and tobacco exposure in a Brazilian RA population. We performed a transversal study comprising 156 RA patients which were investigated for EAM, functional class, presence of anti-CCP2, and IgM rheumatoid factor (IgM-RF). The determination of anti-CCP2 was performed using enzyme immunoassay (ELISA) kits and IgM-RF by latex agglutination test. Clinical and demographical data were obtained through review of charts. Anti-CCP positivity intensity was directly correlated with tobacco smoking, sex, and the development of rheumatoid nodules. Intense anti-CCP2 reaction was 19.8-fold higher in females vs. males, 2.7-fold higher in tobacco vs. non-tobacco users, 7.7-fold higher in female vs. male tobacco users, and 5.15-fold higher in patients with rheumatoid nodules. Tobacco smoking, gender, and rheumatoid nodules are significantly correlated with anti-CCP2 positivity in Brazilian RA patients.